A problem associated with metallic belt reinforced tires is wire corrosion. As noted in U.S. Pat. No. 2,792,868 the problem of corrosion is due to the fact that the metallic wires disposed within the tire are in an environment wherein because of the permeability of elastomers to water vapor, corrosion is apt to take place. This is particularly the case if small amounts of moisture gain entrance to the interior of the tire carcass. The corrosive pitting of metallic surfaces such as the surface of a steel wire can cause corrosion fatigue failure.
Corrosive pits in the surface of corrosion susceptible wires such as steel wires serve as points of localized stress as the wires are continually flexed during normal operating deflection of the tire. This condition leads to eventual breakage of the wires in the belt, thus reducing the strength thereof.
The tire manufacture art has experienced difficulty in dealing effectively with the problem of corrosion in metallic wires of belted tires. In an attempt to avoid corrosion, substitution of non-corrosive wire such as aluminum in place of steel wire has been suggested. However, chemical pretreatment of corrosion susceptible wire belting has been excluded as a solution for the corrosion problem, because the metallic surface modification which is beneficial in inhibiting corrosion is detrimental to bonding of elastomer to the metal wiring.
As noted by reference to U.S. Pat. Nos. 3,676,256; 3,480,508; 3,425,886; 3,423,270; 2,987,095 and 2,912,355, there has been a continual effort to improve adhesion of an elastomer to metallic wiring within a tire carcass. Accordingly any viable solution to the problem of corrosion inhibition cannot adversely affect the bonding of elastomer to metal within the tire.